Fitting ACE structural equation models to case-control family data

Fitting ACE structural equation models to case-control family data.

Investigators interested in whether a disease aggregates in families often collect case-control family data, which consist of disease status and covariate information for members of families selected via case or control probands. Here, we focus on the use of case-control family data to investigate the relative contributions to the disease of additive genetic effects (A), shared family environme...

Fitting Models to Grouped Data

Analytic approaches to twin data using structural equation models

The classical twin study is the most popular design in behavioural genetics. It has strong roots in biometrical genetic theory, which allows predictions to be made about the correlations between observed traits of identical and fraternal twins in terms of underlying genetic and environmental components. One can infer the relative importance of these 'latent' factors (model parameters) by struct...

Fitting exponential family mixed models

The seminal papers by Nelder and Wedderburn (Generalized Linear Models, JRSS A 1972) and Cox (Regression models and life tables, JRSS B 1972) both rely on the assumption that conditionally on covariate information (including time) the observations are independent. The difficulty in identifying and measuring all relevant covariates has pushed for methods that can handle both mean and covariance ...

Fitting Multivariage Normal Finite Mixtures Subject to Structural Equation Modeling

This paper is about fitting multivariate normal mixture distributions subject to structural equation modeling. The general model comprises common factor and structural regression models. The introduction of covariance and mean structure models reduces the number of parameters to be estimated in fitting the mixture and enables one to investigate a variety of substantive hypotheses concerning the...